A power electronic device with high heat loss is required to be cooled, an air cooling manner is usually adopted for a power electronic device at present, and is implemented by mounting a facility such as a blower and a fan for cooling, but its cooling effect is poor, and there exists many problems; a cooling speed of air cooling is low, and the blower is large in size, which may cause a large size of the whole equipment; a large air volume may cause loud noise produced by the blower; reliability of components of the power electronic device is influenced by dust accumulation; the cooling blower is poor in adjustability, high in energy consumption and energy-consuming; and temperature of a mounting environment of the power electronic device is increased by exhaust of the blower, so that it is necessary to add a corresponding air conditioning system in a machine room.